Two commonly used blind stitch machines are the U.S. Blind Stitch Machine and the Lewis Machine. Both of the machines are well known to those skilled in the art. Blind stitch machines are extensively used for seaming and sew a single threaded chain stitch. On seams, it is necessary to perform a tacking operation at the end of the stitch. To shorten the stitch on a standard blind stitch machine, a manual operation is required, taking up some time for the shortening and lengthening again. In U.S. Pat. No. 4,114,547 an attempt is made to provide a stitch shortening device by dropping the platen and loosening the hold of the drive teeth on the material. Hopefully, this will allow tacking by slipping the drive. However, this method is uncertain, and hit or miss, varying with the thickness and type of material.